Objectives: To evaluate the efficacy of low-intensity focused ultrasound (LIFU) treatment on rapid relief of delayed-onset muscle soreness (DOMS) triggered by high-intensity exercise.
Methods: A total of 16 healthy male college students were randomly divided into two groups: the LIFU group (n = 8) and the Sham group (n = 8). After the exercise protocol, the LIFU group received treatment, which parameters included that the power output was 2.5 W/cm2 , the frequency was 1 MHz, and the treating time was 20 minutes. The Sham group was treated with LIFU without energy output. Visual analog scale was used to evaluate the level of DOMS in every participant. The activities of plasma creatine kinase, lactate dehydrogenase, and the plasma concentration were measured by spectrophotometry. Tumor necrosis factor-α and interleukin-6 of serum were analyzed by enzyme-linked immunosorbent assay.
Results: The visual analog scale of quadriceps femoris and/or calf muscles in the LIFU group decreased significantly at 24 hours (P < 0.01) and 48 hours (P < .01) after the exercise protocol. Both the accumulation of lactic acid (P < .01) in muscle and the activity of lactate dehydrogenase (P < .01) reduced immediately after LIFU treatment. The activities of tumor necrosis factor-α and interleukin-6 24 hours lowered in the LIFU group (P < .01).
Conclusions: LIFU treatment could relieve muscle soreness rapidly and effectively in the early stages of DOMS. The application of LIFU may provide a potential strategy for clinical treatment for DOMS.
Keywords: delayed-onset muscle soreness; exercise-induced muscle damage; high-intensity exercise; inflammation response; low-intensity focused ultrasound.
© 2021 American Institute of Ultrasound in Medicine.